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  <title>Document</title>
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<body>
  <script>
    var arr2 = [10, 5, 11, 7, 8, 9]
    function findMaxProfit(arr) {
      var max = arr[0];
      var min = arr[1]
      for (var i = 0; i < arr.length; i++) {
        if (arr[i] > max) {
          max = arr[i]
        }
        if (arr[i] < min) {
          max = min
        }
      }
      return max - min
    }
    console.log(findMaxProfit(arr2));

  </script>
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